Technical Field
The present invention relates to an inter-vehicle control apparatus.
Related Art
An inter-vehicle control apparatus that controls an inter-vehicle distance between an own vehicle and a preceding vehicle is known in related art (for example, refer to JP-A-2000-108720). For example, the inter-vehicle control apparatus detects the inter-vehicle distance between an own vehicle and a preceding vehicle using a radar apparatus. Based on the detected inter-vehicle distance, the inter-vehicle control apparatus then performs acceleration control of the vehicle so that the inter-vehicle distance becomes closer to a target inter-vehicle distance. In another example, the inter-vehicle control apparatus controls the inter-vehicle distance by performing acceleration control of the vehicle so that an inter-vehicle time, which is derived by dividing the detected inter-vehicle distance by the speed of the own vehicle, becomes closer to a target inter-vehicle time.
In the above-described related art, the driver may perform an override operation, thereby approaching the preceding vehicle. An actual inter-vehicle physical quantity corresponding to the detected inter-vehicle distance or inter-vehicle time may become smaller than a target inter-vehicle physical quantity corresponding to the target inter-vehicle distance or inter-vehicle time.
In this instance, the target inter-vehicle physical quantity is changed so as to become closer to the actual inter-vehicle physical quantity, and then is gradually increased over time, thereby controlling the degree of deceleration of the vehicle. The target inter-vehicle physical quantity is changed to become closer to the target inter-vehicle physical quantity that should actually be realized, as the relative speed between the own vehicle and the preceding vehicle decreases. The target inter-vehicle physical quantity is changed to become closer to the actual inter-vehicle physical quantity, as the relative speed between the own vehicle and the preceding vehicle increases.
In the related art, the degree of deceleration is suppressed as described above, and then, driving experience is improved. The following can be considered as instances in which the actual inter-vehicle physical quantity becomes smaller than the target inter-vehicle physical quantity. For example, a new preceding vehicle cuts in ahead of the own vehicle. Alternatively, the target inter-vehicle physical quantity is changed to a large value as a result of change in operating mode.
In the above-mentioned related art, the degree of deceleration is suppressed by the target inter-vehicle physical quantity being changed. For example, when a new preceding vehicle cuts in ahead of the own vehicle and the inter-vehicle distance discontinuously changes, an unnecessarily large degree of deceleration may occur. The following can be given as an example of when an unnecessarily large degree of deceleration occurs. For example, an excessively large amount of deceleration, which is disproportionate to the risk of collision with the preceding vehicle felt by the driver, may occur, thereby causing the driver some discomfort. In this way, the above-mentioned related art has room for improvement regarding the driving feeling.